Firefox - Remove dotted line around links

Oh, how annoying that dotted line around linked elements in Firefox is! Dotted line around links. Courtesy sonspring.com There are many articles describing how to remove it for your website. I don't like the idea - it should be up to the user to decide. So I, as a user, decided to remove them from my browser. How?
  1. Type about:config in Firefox address bar.
  2. If it displays a warning, confirm you know what you're doing.
  3. Find this property (you can use the filter): browser.display.focus_ring_width
  4. Set its value to 0 (zero).


[FIXED] VirtualBox kernel driver not installed rc 1908

This time this helped with my VirtualBox problems (Ubuntu host, Windows guest).
sudo dkms install virtualbox/4.1.2
sudo modprobe vboxdrv